The present invention relates to an imaging device and more particular to an imaging device having combined imaging and projecting capabilities.
Nowadays, many electronic appliances are available which have imaging and in particular image recording capabilities. One objective in further developing known opto-electronic appliances is to reduce the size of such appliances, on the one hand, and to improve the functionalities of these appliances, on the other hand, in particular with respect to the plurality or multiplicity of different functions.
It is an object of the present invention to provide an imaging device which is further decreased in size and further increased with respect to the plurality of its functions.
The object is achieved with an imaging device according to claim 1. preferred embodiment of the inventive imaging device are within the scope of the dependent subclaims.
According to the present invention the proposed image device is adapted for optically imaging in a first imaging mode an object to be imaged so as to generate at least one real object image corresponding to said object. Additionally, according to the invention the imaging device is adapted for optically projecting in a second imaging mode a display image so as to generate at least one real projection image corresponding to said display image.
It is therefore a basic idea of the present invention to combine in one single imaging device imaging or recording capabilities with projecting capabilities. Therefore. only one device is necessary to image an object to generate at least one real object image which corresponds to said object and to optically project a given display image to be projected. In contrast, the prior art needs at least two devices to realize both purposes of imaging and of projecting. For instance for imaging a camcorder is involved, and for projecting an image projector is involved.
According to a preferred embodiment of the inventive imaging device said imaging device is adapted for externally projecting said display image so as to obtain an external real projection image. Therefore, the inventive imaging device can be used to generate a projection image on an external screen, or the like.
In accordance with a further preferred embodiment of the present invention, the inventive imaging device is provided with an optical objective arrangement. Said optical objective arrangement or a part thereof is adapted to be used or to work in said first imaging mode as an image recording objective or a camera objective or as a part thereof. Additionally, said optical objective arrangement or a part thereof is adapted to be used or to work in a said second imaging mode as an image projecting objective or as a projector objective or as a part thereof. Therefore, according to this particular measure parts of the inventive imaging device can be used for different working modes. Consequently, the number of components and therefore the space necessary for realizing the invention are reduced.
It is of particular advantage, that the inventive image device is adapted for generating said object image in an analogue or digital manner.
For realizing the generation and/or the recording of said real object image, image sensor means are provided.
According to an advantageous embodiment of the present invention said image sensor means comprises at least one charge-coupled device. Also a plurality of charge-coupled devices, for instance for different spectral components or colours, may be provided.
Alternatively or additionally, it is advantageous to provide storage means for storing said object image, said display image, derivatives thereof and/or corresponding image information thereof.
According to a further preferred advantageous embodiment an evaluation/control unit is provided for controlling at least said first and second imaging modes.
Additionally, said evaluation/control unit may be adapted to extract, in particular from said image sensor means, to evaluate and/or to store on said storage means image information corresponding to said real object image.
Further, said evaluation/control unit may be adapted to control the formation of said projection image, in particular based on image information, in particular stored and read from said storage means and/or in particular externally supplied, corresponding to said display image to be projected.
According to a further preferred embodiment of the invention an illumination unit is provided for optically projecting together with said optical objective arrangement, in particular in the second imaging mode, said display image so as to obtain said projection image.
It is of further advantage if said illumination unit is adapted to be controlled by said evaluation/control unit and/or by said storage means.
Further, said illumination unit advantageously comprises a light source device appropriate for projection purposes, in particular a high pressure gas discharge lamp arrangement, a LED arrangement and/or the like.
Further, said illumination unit comprises a light valve device, in particular a micro-display, a LCD-device, a liquid-crustal-on-silicon (LcoS) device, and/or a digital mirror device (DMD), for generating said display image or a preform thereof, in particular based on said corresponding image information.
In the inventive imaging device said light valve device may comprise a single light valve for all fundamental colours or one light valve for each of said fundamental colours.
The inventive imaging device is preferable adapted to display images currently taken and/or previously recorded to a spectator by displaying in a viewfinder mode respective images by means of provided viewfinder optics.
Said viewfinder optics may comprise a viewfinder screen for generating a real image.
Alternatively, said viewfinder optics may comprise a viewfinder eyepiece for generating a virtual image.
preferably, the inventive imaging device is adapted to process a plurality of images, in particular sequences thereof or movies.
It is of further advantage if the inventive imaging device is formed as a camcorder device having projector capabilities.
These and further aspects of the present invention will be now explained in more detail based on the following remarks:
A device is presented which e. g. records video pictures like a camcorder andxe2x80x94e. g. after recording xe2x80x94can project the video pictures onto a screen. Both application modesxe2x80x94camera and projectorxe2x80x94may share the same lens for both, imaging the pictures and projecting the pictures. Additionally, parts of the projection unit can be used as electronic viewfinder.
In the camcorder mode an objective lens is used to form a real image of a subject onto an image sensor, e. g. CCD (Charge Coupled Device). The image is recorded, analogue or digitally, and stored on a memory device or storage means. A provided electronic viewfinder may be used for giving immediate feedback of the recorded scene. In viewfinders the picture is displayed on a small-sized display, e. g. TFT-LCD (Thin Film Transistor driven Liquid Crystal Display) or LCoS (Liquid Crystal on Silicon. Reflective display type).
In the projector mode one or more display devices, e. g. pSI-LCD (Poly-Silicon driven Liquid Crystal Display, Transmissive display type), LCoS (Liquid Crystal on Silicon, Reflective display type) or DMD (Digital Mirror Device, Reflective display type) may be used to display a picture which is imaged by means of a projection objective onto a screen. A lamp with sufficient lumen output and an optical illumination unit with good efficiency is necessary in order to illuminate the display device and to get a bright screen image.
A polarizing beam splitter PBS transmitting one polarization component of light and reflecting the complementary one can be used in these modes. Electronic half-wave retarders which can switch the polarization direction of polarized light may be involved. They usually consist of an aligned liquid crystal layer filled between two glass plates and can switch their optical properties by applying an electrical field.
Known video projectors and camcorders are separate devices. This invention describes how to integrate the device concepts into one device. Components of the device are shared for both purposes to save space, weight and cost.